7 files changed, 246 insertions, 1 deletions
diff --git a/tools/build/feature/Makefile b/tools/build/feature/Makefile
index 463ed8f2a267..1c0d69f44552 100644
--- a/tools/build/feature/Makefile
+++ b/tools/build/feature/Makefile
@@ -33,7 +33,8 @@ FILES=					\
 	test-compile-32.bin		\
 	test-compile-x32.bin		\
 	test-zlib.bin			\
-	test-lzma.bin
+	test-lzma.bin			\
+	test-bpf.bin
 
 CC := $(CROSS_COMPILE)gcc -MD
 PKG_CONFIG := $(CROSS_COMPILE)pkg-config
@@ -156,6 +157,9 @@ test-zlib.bin:
 test-lzma.bin:
 	$(BUILD) -llzma
 
+test-bpf.bin:
+	$(BUILD)
+
 -include *.d
 
 ###############################
diff --git a/tools/build/feature/test-bpf.c b/tools/build/feature/test-bpf.c
new file mode 100644
index 000000000000..062bac811af9
--- /dev/null
+++ b/tools/build/feature/test-bpf.c
@@ -0,0 +1,18 @@
+#include <linux/bpf.h>
+
+int main(void)
+{
+	union bpf_attr attr;
+
+	attr.prog_type = BPF_PROG_TYPE_KPROBE;
+	attr.insn_cnt = 0;
+	attr.insns = 0;
+	attr.license = 0;
+	attr.log_buf = 0;
+	attr.log_size = 0;
+	attr.log_level = 0;
+	attr.kern_version = 0;
+
+	attr = attr;
+	return 0;
+}
diff --git a/tools/lib/bpf/.gitignore b/tools/lib/bpf/.gitignore
new file mode 100644
index 000000000000..812aeedaea38
--- /dev/null
+++ b/tools/lib/bpf/.gitignore
@@ -0,0 +1,2 @@
+libbpf_version.h
+FEATURE-DUMP
diff --git a/tools/lib/bpf/Build b/tools/lib/bpf/Build
new file mode 100644
index 000000000000..a316484233c9
--- /dev/null
+++ b/tools/lib/bpf/Build
@@ -0,0 +1 @@
+libbpf-y := libbpf.o
diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
new file mode 100644
index 000000000000..f68d23a0b487
--- /dev/null
+++ b/tools/lib/bpf/Makefile
@@ -0,0 +1,195 @@
+# Most of this file is copied from tools/lib/traceevent/Makefile
+
+BPF_VERSION = 0
+BPF_PATCHLEVEL = 0
+BPF_EXTRAVERSION = 1
+
+MAKEFLAGS += --no-print-directory
+
+
+# Makefiles suck: This macro sets a default value of $(2) for the
+# variable named by $(1), unless the variable has been set by
+# environment or command line. This is necessary for CC and AR
+# because make sets default values, so the simpler ?= approach
+# won't work as expected.
+define allow-override
+  $(if $(or $(findstring environment,$(origin $(1))),\
+            $(findstring command line,$(origin $(1)))),,\
+    $(eval $(1) = $(2)))
+endef
+
+# Allow setting CC and AR, or setting CROSS_COMPILE as a prefix.
+$(call allow-override,CC,$(CROSS_COMPILE)gcc)
+$(call allow-override,AR,$(CROSS_COMPILE)ar)
+
+INSTALL = install
+
+# Use DESTDIR for installing into a different root directory.
+# This is useful for building a package. The program will be
+# installed in this directory as if it was the root directory.
+# Then the build tool can move it later.
+DESTDIR ?=
+DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'
+
+LP64 := $(shell echo __LP64__ | ${CC} ${CFLAGS} -E -x c - | tail -n 1)
+ifeq ($(LP64), 1)
+  libdir_relative = lib64
+else
+  libdir_relative = lib
+endif
+
+prefix ?= /usr/local
+libdir = $(prefix)/$(libdir_relative)
+man_dir = $(prefix)/share/man
+man_dir_SQ = '$(subst ','\'',$(man_dir))'
+
+export man_dir man_dir_SQ INSTALL
+export DESTDIR DESTDIR_SQ
+
+include ../../scripts/Makefile.include
+
+# copy a bit from Linux kbuild
+
+ifeq ("$(origin V)", "command line")
+  VERBOSE = $(V)
+endif
+ifndef VERBOSE
+  VERBOSE = 0
+endif
+
+ifeq ($(srctree),)
+srctree := $(patsubst %/,%,$(dir $(shell pwd)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+srctree := $(patsubst %/,%,$(dir $(srctree)))
+#$(info Determined 'srctree' to be $(srctree))
+endif
+
+FEATURE_DISPLAY = libelf libelf-getphdrnum libelf-mmap bpf
+FEATURE_TESTS = libelf bpf
+
+INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/arch/$(ARCH)/include/uapi -I$(srctree)/include/uapi
+FEATURE_CHECK_CFLAGS-bpf = $(INCLUDES)
+
+include $(srctree)/tools/build/Makefile.feature
+
+export prefix libdir src obj
+
+# Shell quotes
+libdir_SQ = $(subst ','\'',$(libdir))
+libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
+plugin_dir_SQ = $(subst ','\'',$(plugin_dir))
+
+LIB_FILE = libbpf.a libbpf.so
+
+VERSION		= $(BPF_VERSION)
+PATCHLEVEL	= $(BPF_PATCHLEVEL)
+EXTRAVERSION	= $(BPF_EXTRAVERSION)
+
+OBJ		= $@
+N		=
+
+LIBBPF_VERSION = $(BPF_VERSION).$(BPF_PATCHLEVEL).$(BPF_EXTRAVERSION)
+
+# Set compile option CFLAGS
+ifdef EXTRA_CFLAGS
+  CFLAGS := $(EXTRA_CFLAGS)
+else
+  CFLAGS := -g -Wall
+endif
+
+ifeq ($(feature-libelf-mmap), 1)
+  override CFLAGS += -DHAVE_LIBELF_MMAP_SUPPORT
+endif
+
+ifeq ($(feature-libelf-getphdrnum), 1)
+  override CFLAGS += -DHAVE_ELF_GETPHDRNUM_SUPPORT
+endif
+
+# Append required CFLAGS
+override CFLAGS += $(EXTRA_WARNINGS)
+override CFLAGS += -Werror -Wall
+override CFLAGS += -fPIC
+override CFLAGS += $(INCLUDES)
+
+ifeq ($(VERBOSE),1)
+  Q =
+else
+  Q = @
+endif
+
+# Disable command line variables (CFLAGS) overide from top
+# level Makefile (perf), otherwise build Makefile will get
+# the same command line setup.
+MAKEOVERRIDES=
+
+export srctree OUTPUT CC LD CFLAGS V
+build := -f $(srctree)/tools/build/Makefile.build dir=. obj
+
+BPF_IN    := $(OUTPUT)libbpf-in.o
+LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
+
+CMD_TARGETS = $(LIB_FILE)
+
+TARGETS = $(CMD_TARGETS)
+
+all: $(VERSION_FILES) all_cmd
+
+all_cmd: $(CMD_TARGETS)
+
+$(BPF_IN): force elfdep bpfdep
+	$(Q)$(MAKE) $(build)=libbpf
+
+$(OUTPUT)libbpf.so: $(BPF_IN)
+	$(QUIET_LINK)$(CC) --shared $^ -o $@
+
+$(OUTPUT)libbpf.a: $(BPF_IN)
+	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
+
+define update_dir
+  (echo $1 > $@.tmp;				\
+   if [ -r $@ ] && cmp -s $@ $@.tmp; then	\
+     rm -f $@.tmp;				\
+   else						\
+     echo '  UPDATE                 $@';	\
+     mv -f $@.tmp $@;				\
+   fi);
+endef
+
+define do_install
+	if [ ! -d '$(DESTDIR_SQ)$2' ]; then		\
+		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2';	\
+	fi;						\
+	$(INSTALL) $1 '$(DESTDIR_SQ)$2'
+endef
+
+install_lib: all_cmd
+	$(call QUIET_INSTALL, $(LIB_FILE)) \
+		$(call do_install,$(LIB_FILE),$(libdir_SQ))
+
+install: install_lib
+
+### Cleaning rules
+
+config-clean:
+	$(call QUIET_CLEAN, config)
+	$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
+
+clean:
+	$(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so $(VERSION_FILES) .*.d \
+		$(RM) LIBBPF-CFLAGS
+	$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP
+
+
+
+PHONY += force elfdep bpfdep
+force:
+
+elfdep:
+	@if [ "$(feature-libelf)" != "1" ]; then echo "No libelf found"; exit -1 ; fi
+
+bpfdep:
+	@if [ "$(feature-bpf)" != "1" ]; then echo "BPF API too old"; exit -1 ; fi
+
+# Declare the contents of the .PHONY variable as phony.  We keep that
+# information in a variable so we can use it in if_changed and friends.
+.PHONY: $(PHONY)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
new file mode 100644
index 000000000000..c08d6bca1c22
--- /dev/null
+++ b/tools/lib/bpf/libbpf.c
@@ -0,0 +1,14 @@
+/*
+ * Common eBPF ELF object loading operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <asm/unistd.h>
+#include <linux/bpf.h>
+
+#include "libbpf.h"
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
new file mode 100644
index 000000000000..a6f46d908097
--- /dev/null
+++ b/tools/lib/bpf/libbpf.h
@@ -0,0 +1,11 @@
+/*
+ * Common eBPF ELF object loading operations.
+ *
+ * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
+ * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
+ * Copyright (C) 2015 Huawei Inc.
+ */
+#ifndef __BPF_LIBBPF_H
+#define __BPF_LIBBPF_H
+
+#endif